Brad Manhattan Beach
Viper Owner
Mark:
I've heard numbers between 11 to 14% tossed around.
I've heard numbers between 11 to 14% tossed around.
Quick question
- Thread starter Brad Manhattan Beach
- Start date
Mike Brunton
Enthusiast
The most common "accepted loss" for a manual like the T56 I've seen is 15%.... HOWEVER.... I've seen a test where Sean Roe did a engine dyno then a chassis dyno and found about a 12% loss. 13% is probably real close also.
Driveline losses are dependent on a LOT of things - including temperature, RPM and other things. 13% however is reasonably accurate.
Driveline losses are dependent on a LOT of things - including temperature, RPM and other things. 13% however is reasonably accurate.
Doug Supercharged Vipers
Enthusiast
Hey gang --
Don't forget about another culprit that results in greater losses....
Heavier half shafts may result in greater losses. High horsepower cars may utilize even bigger shafts that can rob horsepower. The stock shafts weigh an approximate 14.5 lbs each. The massive shafts on my car weigh 22+lbs each!
I am in currently in the process of working and testing shafts that can handle well over 1000 lbs of torque. The most interesting advantage about these new shafts is that they weigh only 10 lbs each. They will handle the same power as the biggest shafts on the market today and weigh less than half the weight... At least I hope so
Best Regards,
Doug
Don't forget about another culprit that results in greater losses....
Heavier half shafts may result in greater losses. High horsepower cars may utilize even bigger shafts that can rob horsepower. The stock shafts weigh an approximate 14.5 lbs each. The massive shafts on my car weigh 22+lbs each!
I am in currently in the process of working and testing shafts that can handle well over 1000 lbs of torque. The most interesting advantage about these new shafts is that they weigh only 10 lbs each. They will handle the same power as the biggest shafts on the market today and weigh less than half the weight... At least I hope so
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Best Regards,
Doug
Supercharged Vipermad
Enthusiast
I wouldn't expect half-shaft weight to make much of a difference to HP -- even though they're rotating mass, they have a very small diameter relative to other rotating parts (wheels, flywheel, brake rotors) and thus a relatively small contribution to polar moment of inertia in the driveline. Of course, I'd be interested to see evidence to the contrary.
Cheers,
Ben "big heavy half-shaft" Treynor
Cheers,
Ben "big heavy half-shaft" Treynor
Tom Welch
Enthusiast
Ben,
For the record your shafts are no heavier than stock. At least according to my scale.
Tom
BTW, what folks are forgeting about when considering driveline loss for a viper is the IRS(independent Rear Suspension)
Anytime there is possible slack in a drivetrain there is torque loss. A Solid axle version of a manual transmission car should have a driveline loss of 12%. The viper is 15% due to the IRS.
Just my $.02 as im sure others may disagree. I suggest though that you look in the Mopar Chassis Tuners Manual at the formulas for dragstrip HP. They are very accurate, and calculate rear wheel actual hp from the MPH of a 1/4 mile pass.
For the record your shafts are no heavier than stock. At least according to my scale.
Tom
BTW, what folks are forgeting about when considering driveline loss for a viper is the IRS(independent Rear Suspension)
Anytime there is possible slack in a drivetrain there is torque loss. A Solid axle version of a manual transmission car should have a driveline loss of 12%. The viper is 15% due to the IRS.
Just my $.02 as im sure others may disagree. I suggest though that you look in the Mopar Chassis Tuners Manual at the formulas for dragstrip HP. They are very accurate, and calculate rear wheel actual hp from the MPH of a 1/4 mile pass.
Doug Supercharged Vipers
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by btreynor:
I wouldn't expect half-shaft weight to make much of a difference to HP -- even though they're rotating mass, they have a very small diameter relative to other rotating parts (wheels, flywheel, brake rotors) and thus a relatively small contribution to polar moment of inertia in the driveline. Of course, I'd be interested to see evidence to the contrary.
Cheers,
Ben "big heavy half-shaft" Treynor<HR></BLOCKQUOTE>
Your probably right, what's a few extra pounds on a dyno anyway? After all, you can't take a dyno down the track with you. I like Toms idea -- Converting the weight of the vehicle and 1/4 mile trap speed to determine true RWHP.
Can somebody tell me what rear wheel horsepower my Viper is?
> 3785 lbs
> 150.61 1/4 mile trap speed
Happy Holidays and thx,
Doug
I wouldn't expect half-shaft weight to make much of a difference to HP -- even though they're rotating mass, they have a very small diameter relative to other rotating parts (wheels, flywheel, brake rotors) and thus a relatively small contribution to polar moment of inertia in the driveline. Of course, I'd be interested to see evidence to the contrary.
Cheers,
Ben "big heavy half-shaft" Treynor<HR></BLOCKQUOTE>
Your probably right, what's a few extra pounds on a dyno anyway? After all, you can't take a dyno down the track with you. I like Toms idea -- Converting the weight of the vehicle and 1/4 mile trap speed to determine true RWHP.
Can somebody tell me what rear wheel horsepower my Viper is?
> 3785 lbs
> 150.61 1/4 mile trap speed
Happy Holidays and thx,
Doug
You must be registered for see images
Doug Supercharged Vipers
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Tom Welch:
Ben,
For the record your shafts are no heavier than stock. At least according to my scale.
Tom
BTW, what folks are forgeting about when considering driveline loss for a viper is the IRS(independent Rear Suspension)
Anytime there is possible slack in a drivetrain there is torque loss. A Solid axle version of a manual transmission car should have a driveline loss of 12%. The viper is 15% due to the IRS.
Just my $.02 as im sure others may disagree. I suggest though that you look in the Mopar Chassis Tuners Manual at the formulas for dragstrip HP. They are very accurate, and calculate rear wheel actual hp from the MPH of a 1/4 mile pass.
<HR></BLOCKQUOTE>
The additional u-joints in IRS cars can rob UP TO : 12 -- 17hp each.
Regards,
Doug
Ben,
For the record your shafts are no heavier than stock. At least according to my scale.
Tom
BTW, what folks are forgeting about when considering driveline loss for a viper is the IRS(independent Rear Suspension)
Anytime there is possible slack in a drivetrain there is torque loss. A Solid axle version of a manual transmission car should have a driveline loss of 12%. The viper is 15% due to the IRS.
Just my $.02 as im sure others may disagree. I suggest though that you look in the Mopar Chassis Tuners Manual at the formulas for dragstrip HP. They are very accurate, and calculate rear wheel actual hp from the MPH of a 1/4 mile pass.
<HR></BLOCKQUOTE>
The additional u-joints in IRS cars can rob UP TO : 12 -- 17hp each.
Regards,
Doug
TX WHOS YOUR DADDY
Enthusiast
- Joined
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DOUG,THE ANSWER IS APX. 975 R.W.H.P. BASED ON THE DATA YOU SUPPLIED.YOUR WEIGHT TO POWER RATIO IS ABOUT 3.75.YOUR ESTIMATED QTR. MILE WOULD BE 9.1 TO 9.2 SECONDS.WHAT WAS YOUR QTR. MILE TIME WITH THE SPRAY AND S.C. ON?HAPPY HOLIDAYS! NORM KOERNER
Chuck 97 GTS
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Doug Supercharged Vipers:
Can somebody tell me what rear wheel horsepower my Viper is?
> 3785 lbs
> 150.61 1/4 mile trap speed
<HR></BLOCKQUOTE>
Here he goes showing off again...
Can somebody tell me what rear wheel horsepower my Viper is?
> 3785 lbs
> 150.61 1/4 mile trap speed
<HR></BLOCKQUOTE>
Here he goes showing off again...
You must be registered for see images
HP = (((MPH / 234)^3) * Weight)where "^3" = Cubed. so....
1009.206 RWHP=(((150.61 / 234) ^3) * 3785 with ~ 9.05 et.
This is a great site....
http://www.prestage.com/carmath/calc_etmph.asp
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Doug Supercharged Vipers:
Can somebody tell me what rear wheel horsepower my Viper is?
> 3785 lbs
> 150.61 1/4 mile trap speed
Happy Holidays and thx,
Doug
<FONT COLOR="#ff0000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Marv S on December 15, 2000 at 23:29</font>
1009.206 RWHP=(((150.61 / 234) ^3) * 3785 with ~ 9.05 et.
This is a great site....
http://www.prestage.com/carmath/calc_etmph.asp
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Doug Supercharged Vipers:
Can somebody tell me what rear wheel horsepower my Viper is?
> 3785 lbs
> 150.61 1/4 mile trap speed
Happy Holidays and thx,
Doug
You must be registered for see images
<HR></BLOCKQUOTE><FONT COLOR="#ff0000" SIZE="1" FACE="Verdana, Arial">This message has been edited by Marv S on December 15, 2000 at 23:29</font>
Doug Supercharged Vipers
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Chuck 97 GTS:
Here he goes showing off again...
<HR></BLOCKQUOTE>
Whooo me?
Regards,
Doug
Here he goes showing off again...
You must be registered for see images
<HR></BLOCKQUOTE>
Whooo me?
You must be registered for see images
Regards,
Doug
Doug Supercharged Vipers
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Marv S:
HP = (((MPH / 234)^3) * Weight)where "^3" = Cubed. so....
1009.206 RWHP=(((150.61 / 234) ^3) * 3785 with ~ 9.05 et.
This is a great site....
http://www.prestage.com/carmath/calc_etmph.asp
Sorry guys,
I was teasing -- I know what my horsepower is. I get a kick out of those online-dyno's, In a "perfect world," they are accurate. The horsepower is more on the mark than the ET.
Thanks for all those that replied!
Best Regards,
Doug
HP = (((MPH / 234)^3) * Weight)where "^3" = Cubed. so....
1009.206 RWHP=(((150.61 / 234) ^3) * 3785 with ~ 9.05 et.
This is a great site....
http://www.prestage.com/carmath/calc_etmph.asp
Sorry guys,
I was teasing -- I know what my horsepower is. I get a kick out of those online-dyno's, In a "perfect world," they are accurate. The horsepower is more on the mark than the ET.
Thanks for all those that replied!
Best Regards,
Doug
Mamba man steve
Enthusiast
If you go to a shop that knows how to use the chassis dyno Dyno Jet and your car is standsrd shift you can do a reverse pulll. Not in reverse but let the dyno pull down the engine in gear and it gives you the horsepower used to run the drive train. In south Florida there is a shop in Boca Street Rods and Classics 561-394-4359 that works on some very exotic cars plus some chassis work. They dyno a lot of SCCA, Drag cars, even motorcycles, and dawarf cars. They also do track set on sports cars. Speak to George he has a world of knowledge in all aspects of racing.
Mike Brunton
Enthusiast
Doug,
I do not believe your RWHP number. Please deliver your car to me for some unbiased and <AHEM> thorough... umm... testing.
I will need it for a few months to verify your 1000RWHP numbers. Don't be surprised if you get it back and it looks like your engine has been swapped with that of a stock GTS.
On a realistic note, WOW, 1000RWHP?? That's absolutley amazing. I'd love to know the details on this car. What are the internals like (if you can divulge that info), and do you have any trouble with that much power?
I do not believe your RWHP number. Please deliver your car to me for some unbiased and <AHEM> thorough... umm... testing.
I will need it for a few months to verify your 1000RWHP numbers. Don't be surprised if you get it back and it looks like your engine has been swapped with that of a stock GTS.
On a realistic note, WOW, 1000RWHP?? That's absolutley amazing. I'd love to know the details on this car. What are the internals like (if you can divulge that info), and do you have any trouble with that much power?
Tom Welch
Enthusiast
I CAN SAY ONLY THIS:
I SAW DOUG'S CAR RUN 150 MPH, IT LOOKED LIKE AT ABOUT 1/2 TRACK SOMEONE LAUNCHED IT FROM A AIRCRAFT CARRIER CATAPULT!!!
Remember that E.T. does NOT indicate horsepower, Miles Per Hour in trap speed over a given distance DOES.
E.T. is a measure of Chassis Efficency. Dougs chassis was not very effecient resulting in his 10.09 e.t.(not his fault as launching 1000 hp on an 8" slick with a manual transmission is not easy)
Just $.02 more of my cents!!
tom
I SAW DOUG'S CAR RUN 150 MPH, IT LOOKED LIKE AT ABOUT 1/2 TRACK SOMEONE LAUNCHED IT FROM A AIRCRAFT CARRIER CATAPULT!!!
Remember that E.T. does NOT indicate horsepower, Miles Per Hour in trap speed over a given distance DOES.
E.T. is a measure of Chassis Efficency. Dougs chassis was not very effecient resulting in his 10.09 e.t.(not his fault as launching 1000 hp on an 8" slick with a manual transmission is not easy)
Just $.02 more of my cents!!
tom
Doug Supercharged Vipers
Enthusiast
>>On a realistic note, WOW, 1000RWHP?? That's absolutley amazing. I'd love to know the details on this car. What are the internals like (if you can divulge that info), and do you have any trouble with that much power?<<
Hi Mike!
Yes, 1000HP at the rear wheels. The engine was built to produce 1,200 horsepower. It's the pride of my Level 3 Supercharger System with a custom built Supercharger and nitrous injected intercooled. The car's a lot of fun to drive on the highway and with 8.1 compression it's as smooth as stock. It has ice cold air, hates clutches, and passes anything but a gas station!
Now Mike, when are we going to have the pleasure of Supercharging your snake
Call me anytime and I'll fill you in on the details.
Best Regards,
Doug 305 249-RACE (7223)
Hi Mike!
Yes, 1000HP at the rear wheels. The engine was built to produce 1,200 horsepower. It's the pride of my Level 3 Supercharger System with a custom built Supercharger and nitrous injected intercooled. The car's a lot of fun to drive on the highway and with 8.1 compression it's as smooth as stock. It has ice cold air, hates clutches, and passes anything but a gas station!
Now Mike, when are we going to have the pleasure of Supercharging your snake
You must be registered for see images
? Call me anytime and I'll fill you in on the details.
Best Regards,
Doug 305 249-RACE (7223)
Doug Supercharged Vipers
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Tom Welch:
I CAN SAY ONLY THIS:
I SAW DOUG'S CAR RUN 150 MPH, IT LOOKED LIKE AT ABOUT 1/2 TRACK SOMEONE LAUNCHED IT FROM A AIRCRAFT CARRIER CATAPULT!!!
Remember that E.T. does NOT indicate horsepower, Miles Per Hour in trap speed over a given distance DOES.
E.T. is a measure of Chassis Efficency. Dougs chassis was not very effecient resulting in his 10.09 e.t.(not his fault as launching 1000 hp on an 8" slick with a manual transmission is not easy)
Just $.02 more of my cents!!
tom
<HR></BLOCKQUOTE>
Thanks Tom --
Of course I have a lot more work done to my car than you do yours.
At Moroso, you proved "you don't need to refinance the house to make your car fast." Your car was a force to be reckoned with!
Doug
I CAN SAY ONLY THIS:
I SAW DOUG'S CAR RUN 150 MPH, IT LOOKED LIKE AT ABOUT 1/2 TRACK SOMEONE LAUNCHED IT FROM A AIRCRAFT CARRIER CATAPULT!!!
Remember that E.T. does NOT indicate horsepower, Miles Per Hour in trap speed over a given distance DOES.
E.T. is a measure of Chassis Efficency. Dougs chassis was not very effecient resulting in his 10.09 e.t.(not his fault as launching 1000 hp on an 8" slick with a manual transmission is not easy)
Just $.02 more of my cents!!
tom
<HR></BLOCKQUOTE>
Thanks Tom --
Of course I have a lot more work done to my car than you do yours.
At Moroso, you proved "you don't need to refinance the house to make your car fast." Your car was a force to be reckoned with!
Doug
Svsi
Enthusiast
Yoo I was at Norwalk,Ohio and seen Roy Terpstra from TNT run 150mph in the 1/4 mile with just Nitrous with out a blower .I was
wondering what the extra weight is for? The stock car weighs
3450 not 3750 that seems like a lot of extra pounds for a drag car.Must be a cage and blower that brings up the pounds also
leaded fuel ?
SVSI
wondering what the extra weight is for? The stock car weighs
3450 not 3750 that seems like a lot of extra pounds for a drag car.Must be a cage and blower that brings up the pounds also
leaded fuel ?
SVSI
Mike Brunton
Enthusiast
Ron - are you saying your car weighs 3450lbs when it goes down the track?
With a 200lb driver, fuel, and the added weight of a supercharger system, 3750lb is a very reasonable weight.
What does your twin turbo car do in the 1/4? How about your supercharged setup? Are they around 150mph also?
If you're going to question others, let's lay all the numbers out there!
With a 200lb driver, fuel, and the added weight of a supercharger system, 3750lb is a very reasonable weight.
What does your twin turbo car do in the 1/4? How about your supercharged setup? Are they around 150mph also?
If you're going to question others, let's lay all the numbers out there!
Doug Supercharged Vipers
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Svsi:
Yoo I was at Norwalk,Ohio and seen Roy Terpstra from TNT run 150mph in the 1/4 mile with just Nitrous with out a blower .I was
wondering what the extra weight is for? The stock car weighs
3450 not 3750 that seems like a lot of extra pounds for a drag car.Must be a cage and blower that brings up the pounds also
leaded fuel ?
SVSI
<HR></BLOCKQUOTE>
A *Knowledgeble Tuner* knows when converting trap speed into horsepower not to leave out the weight of the driver inclusive to the vehicles weight and combined running gear.
>>Nitrous alone<< -- What happened to the stroker motor?
I've personally observed TNT cars run VERY respectable times on the drag strip, Therefore, I would not discount Roys ability to run like a champion!
Regards,
Doug
Yoo I was at Norwalk,Ohio and seen Roy Terpstra from TNT run 150mph in the 1/4 mile with just Nitrous with out a blower .I was
wondering what the extra weight is for? The stock car weighs
3450 not 3750 that seems like a lot of extra pounds for a drag car.Must be a cage and blower that brings up the pounds also
leaded fuel ?
SVSI
<HR></BLOCKQUOTE>
A *Knowledgeble Tuner* knows when converting trap speed into horsepower not to leave out the weight of the driver inclusive to the vehicles weight and combined running gear.
>>Nitrous alone<< -- What happened to the stroker motor?
I've personally observed TNT cars run VERY respectable times on the drag strip, Therefore, I would not discount Roys ability to run like a champion!
Regards,
Doug
Gerald
Enthusiast
ROTFLMAO again!
Gerald
Gerald
Svsi
Enthusiast
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Mike Brunton:
Ron - are you saying your car weighs 3450lbs when it goes down the track?
With a 200lb driver, fuel, and the added weight of a supercharger system, 3750lb is a very reasonable weight.
What does your twin turbo car do in the 1/4? How about your supercharged setup? Are they around 150mph also?
If you're going to question others, let's lay all the numbers out there!
<HR></BLOCKQUOTE>
Mike- We do have a Viper that weighs 3130 with the driver but it is not a drag car. The Turbo car has run 10:10 at148mph we had burnt the clutch on that pass.We are not drag race people,but
after we finish the top speed runs . We will be doing some drag
racing . The engine that is now in the Turbo car will be able
to put the car in the middle 8 sec with reduced wieght and other
changes.Back in 1994 SVSI ran the 1993 R/T10 Twin Turbo 10.05 at
138 mph with a complete stock engine and stock street tires cost
was $14.900.00 .Since then we have reenginered the Twin Turbo System to make it the highest quality and reliable system that
we can . The Supercharged cars that we have done belong to customers. When they decide to drag race them I will let you know
what the times are .I would imagine that the mph should be in the mid to high 140s.For your info SVSI is looking to set a speed
record of 300mph with the Viper so wish us luck . It does take a
lot of horsepower to push the car that fast in three miles also
big quelones to drive it.Happy Holidays and maybe you will get to see us run in the 8 sec times .
Ron
SVSI
Ron - are you saying your car weighs 3450lbs when it goes down the track?
With a 200lb driver, fuel, and the added weight of a supercharger system, 3750lb is a very reasonable weight.
What does your twin turbo car do in the 1/4? How about your supercharged setup? Are they around 150mph also?
If you're going to question others, let's lay all the numbers out there!
<HR></BLOCKQUOTE>
Mike- We do have a Viper that weighs 3130 with the driver but it is not a drag car. The Turbo car has run 10:10 at148mph we had burnt the clutch on that pass.We are not drag race people,but
after we finish the top speed runs . We will be doing some drag
racing . The engine that is now in the Turbo car will be able
to put the car in the middle 8 sec with reduced wieght and other
changes.Back in 1994 SVSI ran the 1993 R/T10 Twin Turbo 10.05 at
138 mph with a complete stock engine and stock street tires cost
was $14.900.00 .Since then we have reenginered the Twin Turbo System to make it the highest quality and reliable system that
we can . The Supercharged cars that we have done belong to customers. When they decide to drag race them I will let you know
what the times are .I would imagine that the mph should be in the mid to high 140s.For your info SVSI is looking to set a speed
record of 300mph with the Viper so wish us luck . It does take a
lot of horsepower to push the car that fast in three miles also
big quelones to drive it.Happy Holidays and maybe you will get to see us run in the 8 sec times .
Ron
SVSI
